The present invention relates to an immersion device for measuring the temperature of a metal with an optical fiber in a metallurgical vessel.
An immersion device for measuring the temperature of a metal with an optical fiber in a metallurgical vessel is known from EP 2 799 824 A1. More particularly, EP 2 799 824 A1 discloses a robotic immersion device for measuring the temperature in a metallurgical vessel using a molten metal-immersed consumable optical fiber and immersion equipment capable of inserting a temperature device through a side wall of an EAF to a predictable molten steel immersion depth with a temperature-to-temperature measuring frequency of less than 20 seconds. The robotic immersion device comprises a disposable guiding tube having an immersion end and a second end, opposite to the immersion end. An optical fiber can be partially arranged in the disposable guiding tube, whereby the inner diameter of the disposable guiding tube is larger than the outer diameter of the optical fiber which is, as a rule, metal coated. An elastic plug is arranged at the second end of or within the disposable guiding tube, whereby the optical fiber is fed through the elastic plug and whereby the elastic plug reduces a gap between the optical fiber and the disposable guiding tube. In a first phase, the optical fiber and the immersion end of the disposable guiding tube are immersed into the melt. In a subsequent second phase, the optical fiber is immersed with higher speed and deeper into the melt than the disposable guiding tube for measuring the temperature of the melt. In a subsequent third phase, the optical fiber is withdrawn from the melt and the disposable guiding tube is ejected into the melt. For a further temperature measurement, it is necessary to provide a further disposable guiding tube.
EP 2 799 824 A1 teaches to attach the robotic immersion device to an access panel of a side wall of the furnace. In this environment, the conditions are harsh due to high temperatures. Scrap may fall down and there is, as a rule, very little room to install an immersion device.
A system for making a series of temperature measurements of a molten bath in a container wherein a plurality of expendable temperature-sensing units are adapted to be sequentially introduced into the container for making subsequent temperature measurements is known from U.S. Pat. No. 3,390,578. The system comprises a magazine for a supply of expendable thermocouple units.
It is an objective of the present invention to provide a more appropriate immersion device for measuring the temperature with an optical fiber in a metallurgical vessel.